Safety device for gas conductors



` 23 1940- H. ARQUINT ET Ax. I l 2,187,768

SAFETY DEVICE-FOR GAS CONDUCTORS Filed Jan. 2l, '1935 l f 2f V N j @mw WMA :"atented Jan. 23, 1940 UNITED STATES- 2,187,168, SAFETY DEVICE Eon GAS coNpUcroRs Hans Arquint, Sursee, Switzerland, and Oscar f Kiesel, Munich, Germany Application January 21, 1935, Serial No. 2,748

lnG

4 Claims.

Fig. 1 is a sectional view of one form of con-V struction, l. v

Figs. 2 and 3 are sections, in planes perpendicular to each other, of another form of construction.

Referring rst to the construction shown in Fig, l, the interior of a casing I, circular in'plan, with two tubular nozzles at opposite parts of its circumference, is divided into two chambers 2, 3,

of which the nozzles form parts, rthe nozzle of the chamber 2 being connected to the gas main and the nozzle of the chamber 3 being connected to the service pipes. i be called the supply chamber, is formed by the left hand nozzle and a radial passage leading to a circular compartment at the Vcenter of the casing. It is' therefore considerably smaller than the chamber 3, which may be called the delivery chamber, and the cross-sectional area for the ilow of gas is considerably greater in the chamber 3 than in the chamber 2.

The rim l of the wall of the central compartment and a ledge 5, 6 at the rim of the casing I form seats for a flexible diaphragm 1 forming the floor of a chamber 3 in a cap 3 screwed to the casing. To the center oi' the diaphragm 1, above the seat 4, is fixed a tubular spring housing III, having an opening II at the bottom for communication with the chamber 2 and having also an opening I2 in its wall. The spring housing I3 ts slidably into a socket I3 fixed to the cap 9, and contains a helical spring I4 tending to press the diaphragm against the seat 4. The opening I2 is exposed, when the diaphragm is pressed 1 against its seat 4, but is covered by the wall of `the socket I3 when the diaphragm and housing I are lifted. A screw I5 is screwed into a hole in the cap 9, and has a vent passage I6, I1 for communication between the chamber 8 andthe atmosphere, but the outlet of this passage can be closed by means of a nut I8 screwed down on to a washer I9.

In the cover of the radial passage forming part of the chamber 2 there is a small hole 20 affording permanent communication between the chambers 2 and 3. f

When the diaphragm 1 4is pressed against its 'supply of gas is cut The chamber 2, which may ei-many January 24, 1934 seat 4 communication between the supply chamber 2 and the delivery chamber 3 is limited to the small passage 20, so that the normal working oi from the service pipes. Under normal working conditions, that is to say with full gas pressure in the main and no excessive discharge from the service pipes, `the gas pressure in the chambers2 and 3 lifts the diaphragm 1, so that communication between the two chambers is maintained for flow of gas to 1 the service pipes. A predetermined minimum of gas pressure must, however, exist in both the chambers in order to hold the diaphragm olf its seat 4 against the pressuredof the spring Il.k Normally, when gas is being consumed, the gas pressure in the delivery chamber 3 will be lower than that in the supply chamber 2, but the' lower pressure in the chamber 3 acts on a larger area 'of diaphragm surface than the higher pressure in the chamber 2. If the pressure in either 9o vchamber falls below the critical minimum, the

diaphragm drops and rcuts off the iiow of gas, except vin respect of the small orifice 20. If iniiow to the chamber 2 continues, gas from this chamber flows through the passage II, I2 to the 25 chamber 8 and increases the pressure holding the diaphragm'against its seat 4. For allowing the diaphragmto rise again under gas pressure the nut I8 must be unscrewed so as to open the vent I6, I1. When this is done the diaphragm will rise if there -is normal pressure in the main and no abnormal discharge from the service system, but if there is abnormal discharge the opening of the vent can at most result in temporary lifting of the diaphragm, because the low pressure in the chamber 3 will not support the diaphragm. Hence, normal communication between the chambers 2 and 3 cannot be restored till the conditions of supply and delivery are normal again.

The by-pass orifice '20 enables automatic lift- 40 ing of the diaphragm to be obtained in restoration of normal conditions without attention to the nut I8, provided that the outlets of the service system are closed. For this purpose the nut I8 is left unscrewed. There is then a continuous 45 light flow of gas through the by-pass 20 to the chamber 3, resulting in an increase of pressure therein which will soon lift the diaphragm sufiiciently to close the passage I2 and allow normal flow from the chamber 2 to the chamber 3.

In Figs. 2 and 3 the reference characters designating the like parts as in Fig. 1 are followed by the exponent a. These figures show a modification in which there is a cock 32 traversing the chamber 2a within the valve castingl, so 55 that inilow oi gas can be regulated by turning the cock. The by-pass opening 20* is in this case an axial passage in the coned plug of the cock, and can be cleaned by thrusting into it a rod 33 mounted in the cock and actuated by a spring loaded handle accessible from outside the casing. The retaining nut 34 of the plug is inside the casing, so that it is not accessible Without opening the same, and we may arrange that the nut can only be unscrewed by means of a special key.

It will be understood that the device described may be serviceable in various ways. Each individual consumer provided therewith is safeguarded from accidents or damage due to escape oi' gas on destruction or partial destruction of his service pipes and the authorities controlling the gas mains are able (for instance in the case of a threatened air attack) to extinguish lights by a temporary reduction of pressure in the mains, without risk of accidents due to open taps when the pressure is restored, because Where taps are open the restored pressure will not re-establish connection to the respective service system.

We claim:

1. A gas supply control device to be inserted into a gas main comprising a housing having therein a gas supply chamber, a passage of reduced cross section connecting said supply chamber with the supply part of the main, a gas delivery chamber having a greater cross sectional ilow area than said supply chamber, a passage of reduced cross section connecting said delivery chamber with the delivery part of the main, a constricted by-pass establishing permanent communication between said chambers, and a third chamber superimposed on said supply and delivery chambers, a valve interposed between said supply chamber and said delivery chamber said valve comprising a flexible diaphragm forming a gas tight closure for said superimposed chamber and having one face thereof exposed directly to the gas pressure in the supply and delivery chambers and a spring exerting seating pressure on said diaphragm of force suflicient to overcome a predetermined minimum gas pressure on said diaphragm.

2. A gas supply control device, comprising a housing having therein a gas supply chamber. a gas delivery chamber. a constricted by-pasl establishing permanent communication between said chambers and a third chamber superimposed on said supply and delivery chambers, a valve interposed between said third chamber and said other two chambers said valve forming a gas tight closure for said superimposed chamber and comprising a ilexible diaphragm one face or which is exposed directly to the gas pressure in the supply and delivery chamber, means exerting seating pressure on said diaphragm of force sumcient to overcome a predetermined minimum gas pressure on said diaphragm, means embodying a closable vent leading from said third chamber to atmosphere, there being a passage for flow oi gas trom said supply chamber to said third chamber and means for automatically closing said passage when said diaphragm is unseated.

3. A gas supply control device to be inserted between a gas supply main and a service pipe. comprising a housing having therein a gas supply chamber, a passage connecting said gas supply chamber to said main, a gas delivery chamber and a third chamber superimposed on said supply and delivery chambers, a cock in said passage to regulate the inflow of gas to said supply chamber, said cock having a constricted by-pass therein leading directly to the delivery chamber for establishing' permanent communication between the supply and delivery chambers, a valve interposed between said third chamber and said other two chambers said valve forming a gas tight closure for said superimposed chamber and comprising a flexible diaphragm one face of which is exposed v.directly to the gas pressure in the supply and'I delivery chambers and spring exerting seating pressure on said diaphragm o! force sumcient to overcome a predetermined minimum gas pressure on said diaphragm.

4. A gas supply control device, comprising the combination with the elements claimed in claim 3 of a slidable rod mounted in the plug and a spring loaded exteriorly accessible handle carrying a pin for cleaning the passage in the plug. U

HANS ARQINT. /j oscAR maar.. 

